| #region Copyright notice and license |
| // Copyright 2015, Google Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| #endregion |
| |
| using System; |
| using System.Collections.Generic; |
| using System.Linq; |
| using System.Runtime.InteropServices; |
| using System.Threading; |
| using System.Threading.Tasks; |
| |
| using Grpc.Core.Internal; |
| using Grpc.Core.Logging; |
| using Grpc.Core.Utils; |
| |
| namespace Grpc.Core |
| { |
| /// <summary> |
| /// gRPC Channel |
| /// </summary> |
| public class Channel : IDisposable |
| { |
| static readonly ILogger Logger = GrpcEnvironment.Logger.ForType<Channel>(); |
| |
| readonly GrpcEnvironment environment; |
| readonly ChannelSafeHandle handle; |
| readonly List<ChannelOption> options; |
| readonly string target; |
| bool disposed; |
| |
| /// <summary> |
| /// Creates a channel that connects to a specific host. |
| /// Port will default to 80 for an unsecure channel and to 443 for a secure channel. |
| /// </summary> |
| /// <param name="host">The name or IP address of the host.</param> |
| /// <param name="credentials">Credentials to secure the channel.</param> |
| /// <param name="options">Channel options.</param> |
| public Channel(string host, Credentials credentials, IEnumerable<ChannelOption> options = null) |
| { |
| Preconditions.CheckNotNull(host); |
| this.environment = GrpcEnvironment.GetInstance(); |
| this.options = options != null ? new List<ChannelOption>(options) : new List<ChannelOption>(); |
| |
| EnsureUserAgentChannelOption(this.options); |
| using (CredentialsSafeHandle nativeCredentials = credentials.ToNativeCredentials()) |
| using (ChannelArgsSafeHandle nativeChannelArgs = ChannelOptions.CreateChannelArgs(this.options)) |
| { |
| if (nativeCredentials != null) |
| { |
| this.handle = ChannelSafeHandle.CreateSecure(nativeCredentials, host, nativeChannelArgs); |
| } |
| else |
| { |
| this.handle = ChannelSafeHandle.CreateInsecure(host, nativeChannelArgs); |
| } |
| } |
| this.target = GetOverridenTarget(host, this.options); |
| } |
| |
| /// <summary> |
| /// Creates a channel that connects to a specific host and port. |
| /// </summary> |
| /// <param name="host">The name or IP address of the host.</param> |
| /// <param name="port">The port.</param> |
| /// <param name="credentials">Credentials to secure the channel.</param> |
| /// <param name="options">Channel options.</param> |
| public Channel(string host, int port, Credentials credentials, IEnumerable<ChannelOption> options = null) : |
| this(string.Format("{0}:{1}", host, port), credentials, options) |
| { |
| } |
| |
| /// <summary> |
| /// Gets current connectivity state of this channel. |
| /// </summary> |
| public ChannelState State |
| { |
| get |
| { |
| return handle.CheckConnectivityState(false); |
| } |
| } |
| |
| /// <summary> |
| /// Returned tasks completes once channel state has become different from |
| /// given lastObservedState. |
| /// If deadline is reached or and error occurs, returned task is cancelled. |
| /// </summary> |
| public Task WaitForStateChangedAsync(ChannelState lastObservedState, DateTime? deadline = null) |
| { |
| Preconditions.CheckArgument(lastObservedState != ChannelState.FatalFailure, |
| "FatalFailure is a terminal state. No further state changes can occur."); |
| var tcs = new TaskCompletionSource<object>(); |
| var deadlineTimespec = deadline.HasValue ? Timespec.FromDateTime(deadline.Value) : Timespec.InfFuture; |
| var handler = new BatchCompletionDelegate((success, ctx) => |
| { |
| if (success) |
| { |
| tcs.SetResult(null); |
| } |
| else |
| { |
| tcs.SetCanceled(); |
| } |
| }); |
| handle.WatchConnectivityState(lastObservedState, deadlineTimespec, environment.CompletionQueue, environment.CompletionRegistry, handler); |
| return tcs.Task; |
| } |
| |
| /// <summary> |
| /// Allows explicitly requesting channel to connect without starting an RPC. |
| /// Returned task completes once state Ready was seen. If the deadline is reached, |
| /// or channel enters the FatalFailure state, the task is cancelled. |
| /// There is no need to call this explicitly unless your use case requires that. |
| /// Starting an RPC on a new channel will request connection implicitly. |
| /// </summary> |
| public async Task ConnectAsync(DateTime? deadline = null) |
| { |
| var currentState = handle.CheckConnectivityState(true); |
| while (currentState != ChannelState.Ready) |
| { |
| if (currentState == ChannelState.FatalFailure) |
| { |
| throw new OperationCanceledException("Channel has reached FatalFailure state."); |
| } |
| await WaitForStateChangedAsync(currentState, deadline); |
| currentState = handle.CheckConnectivityState(false); |
| } |
| } |
| |
| /// <summary> |
| /// Destroys the underlying channel. |
| /// </summary> |
| public void Dispose() |
| { |
| Dispose(true); |
| GC.SuppressFinalize(this); |
| } |
| |
| internal string Target |
| { |
| get |
| { |
| return target; |
| } |
| } |
| |
| internal ChannelSafeHandle Handle |
| { |
| get |
| { |
| return this.handle; |
| } |
| } |
| |
| internal CompletionQueueSafeHandle CompletionQueue |
| { |
| get |
| { |
| return this.environment.CompletionQueue; |
| } |
| } |
| |
| internal CompletionRegistry CompletionRegistry |
| { |
| get |
| { |
| return this.environment.CompletionRegistry; |
| } |
| } |
| |
| internal GrpcEnvironment Environment |
| { |
| get |
| { |
| return this.environment; |
| } |
| } |
| |
| protected virtual void Dispose(bool disposing) |
| { |
| if (disposing && handle != null && !disposed) |
| { |
| disposed = true; |
| handle.Dispose(); |
| } |
| } |
| |
| private static void EnsureUserAgentChannelOption(List<ChannelOption> options) |
| { |
| if (!options.Any((option) => option.Name == ChannelOptions.PrimaryUserAgentString)) |
| { |
| options.Add(new ChannelOption(ChannelOptions.PrimaryUserAgentString, GetUserAgentString())); |
| } |
| } |
| |
| private static string GetUserAgentString() |
| { |
| // TODO(jtattermusch): it would be useful to also provide .NET/mono version. |
| return string.Format("grpc-csharp/{0}", VersionInfo.CurrentVersion); |
| } |
| |
| /// <summary> |
| /// Look for SslTargetNameOverride option and return its value instead of originalTarget |
| /// if found. |
| /// </summary> |
| private static string GetOverridenTarget(string originalTarget, IEnumerable<ChannelOption> options) |
| { |
| if (options == null) |
| { |
| return originalTarget; |
| } |
| foreach (var option in options) |
| { |
| if (option.Type == ChannelOption.OptionType.String |
| && option.Name == ChannelOptions.SslTargetNameOverride) |
| { |
| return option.StringValue; |
| } |
| } |
| return originalTarget; |
| } |
| } |
| } |